Innate Immune Function in Influenza-Associated Myopathy

流感相关肌病的先天免疫功能

• 批准号: 10557027
• 负责人: Benjamin L King
• 金额: $ 26.19万
• 依托单位: UNIVERSITY OF MAINE ORONO
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-04-05 至 2028-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10557027
• 关键词: Acetylcysteine; Acute; Adhesions; Antioxidants; Biopsy; Biosensor; Chemotaxis; Creatine Kinase; Cues; Defect; Disease; Embryo; Exhibits; Extensive Necrosis; Extracellular Matrix; Fiber; Focal Infection; Genetic; Glutathione; Goals; Grant; Hospitalization; Hour; Hydrogen Peroxide; Immune system; Individual; Infection; Inflammatory Response; Influenza; Influenza A Virus, H1N1 Subtype; Influenza A virus; Innate Immune System; Integration Host Factors; Invaded; Knowledge; Laboratories; Ligands; Link; Macrophage; Mediating; MicroRNAs; Modeling; Muscle; Muscle Cells; Myelogenous; Myocarditis; Myopathy; Natural Immunity; Neutrophil Activation; Neutrophil Infiltration; Oxidative Stress; Pathogenesis; Pathology; Pathway interactions; Patients; Peroxidases; Population; Production; Regulation; Reporter; Reporting; Respiratory Signs and Symptoms; Role; Sagittaria; Sarcolemma; Serum; Severities; Signal Pathway; Signal Transduction; Site; Skeletal Muscle; Symptoms; System; Testing; Tissues; Transgenes; Viral; Virus; Virus Diseases; Visualization; Zebrafish; biological adaptation to stress; cell behavior; cell growth regulation; cell motility; confocal imaging; design; extracellular; gene regulatory network; in vivo; in vivo imaging; influenza epidemic; influenza infection; influenza virus vaccine; influenzavirus; innate immune function; insight; migration; muscle degeneration; mutant; neutrophil; novel; overexpression; pathogen; recruit; response; strength training; therapy development; tool; transcriptome sequencing

PROJECT SUMMARY / ABSTRACT Skeletal muscle myopathy has been reported following infection by influenza virus. In Influenza-Associated Myopathy (IAM), a systemic influenza infection can result in acute skeletal muscle damage that ranges from non- specific degeneration to extensive necrosis. IAM is associated with high serum creatine kinase (CK) levels. During the 2009 H1N1 influenza epidemic, 62% of hospitalized patients had increased serum CK levels. Given that an estimated 9-45 million individuals acquire influenza infections annually in the US, developing new strategies to reduce muscle damage are needed as influenza vaccines are difficult to design because of unpredictable changes in viral strains within and across populations. The severity of viral disease varies between individuals and depends on how the immune system responds to infection. One roadblock to understanding the pathogenesis of IAM is that the relative contributions of the virus and host factors in vivo are not well understood. Biopsy studies cannot show the temporal dynamics of viral invasion and subsequent recruitment of neutrophils and macrophages into muscle. The zebrafish is a powerful model to study host-pathogen interactions as genetic tools can be combined with in vivo imaging of transparent embryos. My laboratory uses a recently-developed zebrafish model of influenza A virus (IAV) infection where it was shown that: 1) IAV-infected zebrafish embryos exhibited mild muscle degeneration with sarcolemma damage and compromised extracellular matrix (ECM) adhesion; and 2) neutrophils localize to sites of muscle damage in IAV-infected embryos. Our specific goal in this proposal is to determine the mechanisms through which neutrophils influence the pathology of IAM. This project will test the novel hypothesis that overactivation of neutrophils during IAV infection triggers a damaging hyperinflammatory response that contributes to myopathy. In the first aim, we will test the hypothesis that reduction in reactive oxidative species (ROS) production following IAV infection will limit damage by strengthening muscle cell-ECM adhesion, and increase survival. This will be accomplished by examining how global ROS reduction and neutrophil-specific ROS reduction alters muscle degeneration, cell-ECM adhesion, and neutrophil localization in the muscle in vivo using IAV multi-spectral fluorescent reporter (Color-flu) strains. In the second aim, we will test the hypothesis that defects in neutrophil migration following IAV infection will increase muscle degeneration, and weaken ECM adhesion. To accomplish this, we will use in vivo confocal imaging to study two zebrafish mutants with defective neutrophil migration infected with Color-flu to test our hypotheses that: 1) neutrophil invasion into skeletal muscle is reduced, and 2) muscle degeneration is increased and cell-ECM adhesion is increased over controls. One of these mutants overexpresses miR-199 in neutrophils that disrupts neutrophil migration. Proposed RNA sequencing will allow us to determine microRNA gene regulatory networks thereby allowing us to establish a link between IAM and microRNA genetic regulation. Knowledge gained through the study of IAM may inform studies of other viral-associated myopathies.

项目摘要 /摘要 流感病毒感染后，骨骼肌肌病已被报道。与流感相关 肌病（IAM），系统性流感感染会导致急性骨骼肌损伤 广泛坏死的特异性退化。 IAM与高血清肌酸激酶（CK）水平相关。 在2009年H1N1流感流行期间，有62％的住院患者的血清CK水平升高。给出 估计有9-4500万个人每年在美国获得流感感染，开发新的 由于流感疫苗很难设计，因此需要减少肌肉损伤的策略 人群内外病毒菌株的不可预测的变化。病毒疾病的严重程度在 个体并取决于免疫系统如何应对感染。一个障碍，了解 IAM的发病机理是病毒和体内宿主因子的相对贡献尚不清楚。 活检研究不能显示病毒侵袭的时间动力学和随后的中性粒细胞的募集 巨噬细胞成肌肉。斑马鱼是一种研究宿主 - 病原体相互作用作为遗传的强大模型 工具可以与透明胚胎的体内成像结合使用。我的实验室使用了最近开发的 流感病毒（IAV）感染的斑马鱼模型，其中显示为：1）IAV感染的斑马鱼胚胎 表现出轻度的肌肉变性，并带有肌膜损伤和受损的细胞外基质（ECM） 粘附； 2）中性粒细胞位于感染IAV的胚胎中的肌肉损伤部位。我们的具体目标 该建议是确定中性粒细胞影响IAM病理的机制。这 项目将测试新的假设，即IAV感染期间中性粒细胞过度活化会触发破坏性 过度炎症反应会导致肌病。在第一个目的中，我们将检验以下假设 IAV感染后的反应性氧化物种（ROS）产生的减少将限制损害 增强肌肉细胞ECM粘附并增加存活率。这将通过检查如何完成 全球ROS降低和中性粒细胞特异性ROS还原改变了肌肉变性，细胞-ECM粘附， 使用IAV多光谱荧光报告基因（color-Flu）菌株在体内中的嗜中性粒细胞定位。 在第二个目标中，我们将检验以下假设：IAV感染后嗜中性粒细胞迁移的缺陷将 增加肌肉变性，并削弱ECM粘附。为此，我们将使用体内共聚焦 成像研究两个斑马鱼突变体，中性粒细胞迁移有缺陷，感染了颜色-FLU，以测试我们 假设：1）中性粒细胞侵袭骨骼肌，2）肌肉变性增加 在对照组上，细胞ECM粘附量增加。这些突变体之一过表达中性粒细胞中的miR-199 这破坏了中性粒细胞的迁移。提出的RNA测序将使我们能够确定microRNA基因 监管网络因此使我们能够在IAM和MicroRNA遗传调节之间建立联系。 通过对IAM的研究获得的知识可能会为其他病毒相关性肌病的研究提供信息。